From 221975bce81940628660aa264001eaf9cc48dd95 Mon Sep 17 00:00:00 2001
From: Christian <c@ethdev.com>
Date: Mon, 20 Oct 2014 12:41:56 +0200
Subject: [PATCH] Expression compiler.

---
 main.cpp | 41 +++++++++++++++++++++++++++++++++++++++++
 1 file changed, 41 insertions(+)

diff --git a/main.cpp b/main.cpp
index ba0b6ccf7..221ab962e 100644
--- a/main.cpp
+++ b/main.cpp
@@ -10,6 +10,7 @@
 #include <libsolidity/ASTPrinter.h>
 #include <libsolidity/NameAndTypeResolver.h>
 #include <libsolidity/Exceptions.h>
+#include <libsolidity/Compiler.h>
 #include <libsolidity/SourceReferenceFormatter.h>
 
 using namespace dev;
@@ -34,6 +35,35 @@ void version()
 	exit(0);
 }
 
+
+/// Helper class that extracts the first expression in an AST.
+class FirstExpressionExtractor: private ASTVisitor
+{
+public:
+	FirstExpressionExtractor(ASTNode& _node): m_expression(nullptr) { _node.accept(*this); }
+	Expression* getExpression() const { return m_expression; }
+private:
+	virtual bool visit(Expression& _expression) override { return checkExpression(_expression); }
+	virtual bool visit(Assignment& _expression) override { return checkExpression(_expression); }
+	virtual bool visit(UnaryOperation& _expression) override { return checkExpression(_expression); }
+	virtual bool visit(BinaryOperation& _expression) override { return checkExpression(_expression); }
+	virtual bool visit(FunctionCall& _expression) override { return checkExpression(_expression); }
+	virtual bool visit(MemberAccess& _expression) override { return checkExpression(_expression); }
+	virtual bool visit(IndexAccess& _expression) override { return checkExpression(_expression); }
+	virtual bool visit(PrimaryExpression& _expression) override { return checkExpression(_expression); }
+	virtual bool visit(Identifier& _expression) override { return checkExpression(_expression); }
+	virtual bool visit(ElementaryTypeNameExpression& _expression) override { return checkExpression(_expression); }
+	virtual bool visit(Literal& _expression) override { return checkExpression(_expression); }
+	bool checkExpression(Expression& _expression)
+	{
+		if (m_expression == nullptr)
+			m_expression = &_expression;
+		return false;
+	}
+private:
+	Expression* m_expression;
+};
+
 int main(int argc, char** argv)
 {
 	std::string infile;
@@ -92,5 +122,16 @@ int main(int argc, char** argv)
 	std::cout << "Syntax tree for the contract:" << std::endl;
 	dev::solidity::ASTPrinter printer(ast, sourceCode);
 	printer.print(std::cout);
+
+	FirstExpressionExtractor extractor(*ast);
+
+	CompilerContext context;
+	ExpressionCompiler compiler(context);
+	compiler.compile(*extractor.getExpression());
+	bytes instructions = compiler.getAssembledBytecode();
+	// debug
+	std::cout << "Bytecode for the first expression: " << std::endl;
+	std::cout << eth::disassemble(instructions) << std::endl;
+
 	return 0;
 }